Mechanically interlocked molecules, such as rotaxanes and catenanes, are composed of two or more covalent subcomponents threaded through one another such that they cannot be separated without breaking a covalent bond. This arrangement can allow the covalent subcomponents to undergo large-amplitude relative motion, and this property of the mechanical bond has been widely exploited in the design and synthesis of molecular machines. Another less well-known property of the mechanical bond is that it can give rise to chirotopic stereogenic units that do not rely on covalent stereogenic elements. Although the study of such “mechanically chiral” molecules is expanding, their synthesis in enantiopure form remains challenging. In this Perspective, we review the strategies available, highlighting key examples along the way, and suggest future areas for development.

机械互锁的分子，例如轮烷和链烷，是由彼此穿过的两个或多个共价亚组分组成的，因此，如果不破坏共价键，它们就无法分离。这种布置可以使共价亚组分经历大幅度的相对运动，并且机械键的这种性质已经在分子机器的设计和合成中得到了广泛利用。机械键的另一个鲜为人知的特性是，它可以产生不依赖共价立体异构元素的手性立体异构单元。尽管这类“机械手性”分子的研究正在扩展，但它们以对映纯形式合成仍具有挑战性。在本透视图中，我们回顾了可用的策略，重点介绍了其中的关键示例，